The Intel 12th Gen Core i9-12900K Review: Hybrid Performance Brings Hybrid Complexity
by Dr. Ian Cutress & Andrei Frumusanu on November 4, 2021 9:00 AM ESTCPU Benchmark Performance: DDR5 vs DDR4
Traditionally we test our memory settings at JEDEC specifications. JEDEC is the standards body that determines the requirements for each memory standard. In this case, the Core i9 supports the following aligning with those standards:
- DDR4-3200 CL22
- DDR5-4800B CL40*
There's an * next to the DDR5 for a couple of reasons. First, when asked, Intel stated that 4800A (CL34) was the official support, however since the technical documents have now been released, we've discovered that it is 4800B (CL40). Secondly, 4800B CL40 technically only applies to 1 module per 64-bit channel on the motherboard, and only when the motherboard has two 64-bit slots to begin with. We covered Intel's memory support variants in a previous article, and in this instance, we're using DDR5-4800B memory in our testing.
As explained in our SPEC section, DDR5 memory not only brings bandwidth improvements but also the increased number of channels (4x32-bit vs 2x64-bit) means that the memory can be better utilized as threads pile on the memory requests. So while we don't see much improvement in single threaded workloads, there are a number of multi-threaded workloads that would love the increased performance.
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mode_13h - Saturday, November 6, 2021 - link
> Consumers deserve non-broken products that aren’t sold via smoke and mirrors tactics.What's broken, exactly? They said you wouldn't have AVX-512. That someone figured out how to enable it is just bonus.
mode_13h - Saturday, November 6, 2021 - link
Why are you convinced it's so consequential?mode_13h - Saturday, November 6, 2021 - link
Oops, that was a response to:OG> The current situation is inexcusable.
Oxford Guy - Sunday, November 7, 2021 - link
That question is meritless.mode_13h - Sunday, November 7, 2021 - link
If the issue isn't terribly consequential, then why is it inexcusable? The gravity of alleged misconduct usually derives from its impacts.Oxford Guy - Monday, November 8, 2021 - link
I have been suspicious that you’re some sort of IBM AI. Posts like that go a long way toward supporting that suspicion.You were the poster who claimed it’s of little consequence. I was the poster who said it’s inexcusable. Either you’re AI that needs work or your mind is rife with confusion in your quest to impress the community via attempts at domination.
Not a good look, again. Posting your own claims as if they’re mine and using my claims to create a false incompetence situation is a bit better than your pathetic schoolyard taunts. So, perhaps I should praise you for improving the quality of your posts via being merely incompetent — like Intel’s handling of this situation you’re trying to downplay. I shouldn’t make that equivalence, though, as lying to the community in terms of a retail product is worse than any of your parlor tricks.
mode_13h - Tuesday, November 9, 2021 - link
> I have been suspicious that you’re some sort of IBM AI.No way. Their artificial intelligence is no match for my natural stupidity.
:D
> You were the poster who claimed it’s of little consequence.
No, I asked *you* why it's so consequential.
> I was the poster who said it’s inexcusable.
Which sort of implies that it's very consequential. If it's of not, then why would it be inexcusable?
> Either you’re AI that needs work or your mind is rife with confusion in your quest to
> impress the community via attempts at domination.
If you wouldn't waste so much energy posturing and just answer the question, maybe we could actually get somewhere.
I don't honestly care what the community thinks of me. That's the beauty of pseudonymity! I don't even need people to believe I'm somehow affiliated with a prestigious university. Either my points make sense and are well-founded or they aren't. Similarly, I don't care if you're "just" the Oxford garbage collector. If you contribute useful information, then we all win. If you're just trolling, flaming, or pulling the thread into irrelevant tangents, then we all lose.
The main reason I post on here is to share information and to learn. I asked what should be a simple question which you dismissed as meritless, and without explaining why. As usual, only drama ensues, when I try to press the issue. I always want to give people the opportunity to justify their stance, but so often you just look for some way to throw it back in my face.
This kind of crap is extremely low value. I hope you agree.
mode_13h - Saturday, November 6, 2021 - link
> and the sentence about how it could be eliminated in the future.It's true. Intel can disable instructions in microcode updates and in future steppings of the CPU. So, even having the BIOS option is no guarantee.
mode_13h - Saturday, November 6, 2021 - link
> Since the silicon is there, if they can get the scheduler to manage> heterogeneous (P/E) cores there is now no down side with enabling AVX-512.
This will not happen. The OS scheduler cannot compensate for lack of app awareness of the heterogeneous support for AVX-512. I'm sure that was fiercely debated, at Intel, but the performance downsides for naive code (i.e. 99%+ of the AVX-512 code in the wild) would generate too many complaints and negative publicity from the apps where enabling it results in performance & power regressions.
Oxford Guy - Saturday, November 6, 2021 - link
So, Alder Lake is a turkey as a high-end CPU, one that should have never been released? This is because each program has to include Alder Lake AVX-512 support and those that don’t will cause performance regressions?So, Intel designed and released a CPU that it knew wouldn’t be properly supported by Windows 11 — yet the public was sold Windows 11 primarily on the basis of how its nifty new scheduler will support this CPU?
‘The OS scheduler cannot compensate for lack of app awareness of the heterogeneous support for AVX-512’
Is Windows 11 able to support a software utility to disable the low-power cores once booted into Windows or are we restricted to disabling them via BIOS? If the latter is the case then Intel had the responsibility for mandating such a switch for all Alder Lake boards, as part of the basic specification.